On Fri, 9 Sep 2016 14:04:55 +0300
Marcel Apfelbaum <mar...@redhat.com> wrote:
> On 09/09/2016 01:40 PM, Cornelia Huck wrote:
> > On Fri, 9 Sep 2016 12:14:32 +0200
> > Maxime Coquelin <maxime.coque...@redhat.com> wrote:
> >
> >> This patch makes pci devices plugging more robust, by not confusing
> >> guest with modern interface when the backend doesn't support
> >> VIRTIO_F_VERSION_1.
> >>
> >> Cc: Marcel Apfelbaum <mar...@redhat.com>
> >> Cc: Michael S. Tsirkin <m...@redhat.com>
> >> Cc: qemu-sta...@nongnu.org
> >> Signed-off-by: Maxime Coquelin <maxime.coque...@redhat.com>
> >> ---
> >> hw/virtio/virtio-pci.c | 15 +++++++++++++++
> >> hw/virtio/virtio-pci.h | 5 +++++
> >> 2 files changed, 20 insertions(+)
> >
> > Note that 11380b361 ("virtio: handle non-virtio-1-capable backend for
> > ccw") fixes this issue for ccw via the introduction of a
> > ->post_plugged() callback. Unfortunately, we did not find a good way to
> > make it work for pci back then.
>
> It seems that for ccw is enough to rewind dev->rev_max,
> sadly for pci we need to rewind a lot of settings/resources.
Yes, that what I meant with 'more flexibility for ccw'.
>
> Thanks,
> Marcel
>
> >
> > Two comments:
> > - ->post_plugged() handles the dependencies (as noticed for your first
> > patch) - and this is due to it being called after the plugging is
> > already done.
> > - I don't really like pci and ccw being too different. We have probably
> > more flexibility with the handling for ccw, so I could probably convert
> > ccw to the same mechanism that pci uses. Maybe there are other uses for
> > ->post_plugged()?
> >
>
